1. Field of the Invention
This invention relates generally to ball screw arrangements, and more particularly, to a compact recirculating ball linear bearing arrangement wherein ball recirculation is effected within a recess in the ball screw whereby axial translation of the ball screw along the length of an elongated nut is achieved the response to the application of a rotatory drive to the nut.
2. Description of the Related Art
A number of arrangements are available in the prior art wherein a ball screw and nut mechanism include an insert in the nut whereby balls are recirculated in the nut. Other known recirculating ball screw arrangements include a ball recirculating member that cooperates with a lead screw to urge the balls out of their normal track to transfer the balls over the lead screw in an axial direction and then deposit same back onto the ball track.
All of the known arrangements are large in the radial direction and therefore cannot be accommodated in a compact environment. Thus, for example, the known arrangements cannot readily be accommodated within the confines of a drive motor to achieve an arrangement having a compact radial dimension and that facilitates a linear displacements of the ball screw to an extent that corresponds to a significant proportion of the overall axial dimension of the motor drive.
It is, therefore, an object of this invention to provide a compact linear drive arrangement that has a reduced radial dimension requirement.
It is another object of this invention to provide a ball screw arrangement wherein ball recirculation does not require displacement of a ball further radially outward than the helical groove of the race.
It is also an object of this invention to provide an arrangement for facilitating assembly of the compact ball screw arrangement of the present invention.
It is additionally an object of this invention to provide a compact drive arrangement wherein a linear translation bearing is contained within a drive motor system.
It is yet a further object of this invention to provide a compact linear translation bearing arrangement wherein linear translation is achieved from within the motor drive arrangement and extends for a significant portion of the overall length of the drive arrangement.
It is yet an additional object of this invention to provide a splined linear bearing arrangement wherein an actuator element is coupled thereto in rotatively fixed relation, and is axially translatable with respect thereto.